According to recent estimates, heart failure (HF) is one of the most common reasons for hospital admission in the United States. Efforts have been made to reduce the number of hospitalizations related to HF, and several therapies have been developed over the last 20 years that have been shown to reduce disease-related hospitalizations. Furthermore, quality improvement initiatives are being developed and launched to ensure the appropriate delivery of evidence-based therapies in HF.

CMS has been reporting on the quality of care and rate of HF rehospitalization for hospitals in an effort to encourage quality improvement initiatives. “While previous analyses have shown that rates of HF hospitalizations increased in the 1980s and 1990s, more recent CMS data indicate that hospitalizations with a primary diagnosis of HF in the elderly declined over the last decade,” explains Saul B. Blecker, MD, MHS. “These findings have been attributed to improvements in treatment and reductions in prevalent HF. However, most hospitalizations involving these patients are for reasons other than acute HF.”

Gaining Perspective on Secondary HF Hospitalizations

Quality improvement initiatives typically target only hospitalizations with a primary diagnosis of HF. As a result, these initiatives may not affect comorbid conditions that are associated with HF but are not directly caused by it. “Characterizing trends in hospitalizations with HF as a primary or secondary diagnosis can help clinicians further understand and recognize the role of cardiac disease and non-cardiac conditions,” Dr. Blecker says. “It can also help educate future initiatives to improve quality improvement initiatives.”

A study by Dr. Blecker and colleagues published in the Journal of the American College of Cardiology evaluated trends in primary and secondary HF hospitalizations in the U.S. using Nationwide Inpatient Sample data from 2001 to 2009. The number of primary HF hospitalizations decreased from 1,137,944 in 2001 to 1,086,685 in 2009. The percent of all hospitalizations that carried a primary diagnosis of HF decreased from 29.2% to 25.6% during the study period. However, during the same timeframe, secondary HF hospitalizations increased from 2,753,793 to 3,158,179 (Figure 1). Hospitalization rates for non-cardiovascular causes increased from 48.5% to 54.1%.



The percentage of hospitalizations attributable to causes other than HF increased from 2001 to 2009 in the U.S., according to Dr. Blecker. “These hospitalizations accounted for 75% of the total number of HF-related hospitalizations by 2009. The improvements seen during the last decade in primary HF hospitalization rates do not appear to have been realized for all-cause hospitalization. The increase in secondary HF hospitalizations may partly be explained by the high number of rehospitalizations among patients with HF, many of which are for causes other than HF. Our findings suggest that clinical and policy interventions to reduce all-cause rehospitalizations may have been somewhat successful in the last 3 years of the study period, but the effect of such initiatives on post-discharge outcomes deserves further attention.”

More than 16% of all hospitalizations carried a primary diagnosis related to pulmonary disease. Significant increases in the percentage of hospitalizations for renal and infectious diseases were also observed, most notably acute renal failure and sepsis. Among all HF-related hospitalizations, pneumonia was the second most common primary diagnosis after HF, but its prevalence decreased significantly during the study period (Figure 2). Comparable declines in the percentage of hospitalizations were seen for acute myocardial infarction and coronary atherosclerosis. Conversely, other common pulmonary diagnoses—COPD and respiratory failure, in particular—increased from 2001 to 2009.

Reductions in primary HF hospitalizations were not observed in all age groups in the analysis. “Among patients younger than 50, there was no change in the rate of primary HF hospitalizations,” notes Dr. Blecker. “This patient group also had the highest growth in secondary HF hospitalizations. These findings suggest that initiatives to reduce hospitalizations and rehospitalizations among HF patients should make greater efforts to target younger patients.”

Looking Ahead at Improving HF Outcomes

Dr. Blecker says the high rate of comorbid diseases with HF observed in his study team’s analysis is not surprising because many are risk factors for HF. “The presence of more comorbidities worsens outcomes in HF and increases treatment burden, among other consequences. New decision-making and care delivery models are necessary to address the needs of the growing number of patients with HF and comorbid conditions. Recent quality improvement interventions do not appear to have decreased the number of HF-related hospitalizations during the past decade. Future strategies to reduce hospitalizations of HF patients should consider both cardiac disease and non-cardiac comorbid conditions.”